/**
 * Copyright (C) 2002-2015   The FreeCol Team
 * <p>
 * This file is part of FreeCol.
 * <p>
 * FreeCol is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 2 of the License, or
 * (at your option) any later version.
 * <p>
 * FreeCol is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTLIMIT or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * <p>
 * You should have received a copy of the GNU General Public License
 * along with FreeCol.  If not, see <http://www.gnu.org/licenses/>.
 */

package net.sf.freecol.common.model;

import java.util.Collection;
import java.util.Collections;
import java.util.HashMap;
import java.util.Map;

import javax.xml.stream.XMLStreamException;

import net.sf.freecol.common.io.FreeColXMLReader;
import net.sf.freecol.common.io.FreeColXMLWriter;


/**
 * A special game event.
 */
public class Event extends FreeColGameObjectType
{

    /** A restriction on the scope of the event. */
    private String value;

    /** The score value of this event. */
    private int scoreValue = 0;

    /** Limits on this event. */
    private Map< String, Limit > limits = null;


    /**
     * Create a new event.
     *
     * @param id The object identifier.
     * @param specification The <code>Specification</code> to refer to.
     */
    public Event( String id, Specification specification )
    {
        super( id, specification );
    }

    /**
     * Create a new event.
     *
     * @param xr The <code>FreeColXMLReader</code> to read from.
     * @param specification The <code>Specification</code> to refer to.
     * @exception XMLStreamException if there a problem reading the stream.
     */
    public Event( FreeColXMLReader xr, Specification specification ) throws XMLStreamException
    {
        super( specification );

        readFromXML( xr );
    }


    /**
     * Gets the event restriction.
     *
     * @return The restriction.
     */
    public final String getValue( )
    {
        return value;
    }

    /**
     * Sets the event restriction.
     *
     * @param newValue The new event restriction.
     */
    public final void setValue( final String newValue )
    {
        this.value = newValue;
    }

    /**
     * Get the limits on this event.
     *
     * @return A list of limits.
     */
    public final Collection< Limit > getLimits( )
    {
        return ( limits == null ) ? Collections.< Limit >emptyList( )
                : limits.values( );
    }

    /**
     * Gets a particular limit by identifier.
     *
     * @param id The object identifier.
     * @return The corresponding <code>Limit</code> or null if not found.
     */
    public final Limit getLimit( String id )
    {
        return ( limits == null ) ? null : limits.get( id );
    }

    /**
     * Add a limit.
     *
     * @param limit The <code>Limit</code> to add.
     */
    private void addLimit( Limit limit )
    {
        if ( limits == null ) limits = new HashMap<>( );
        limits.put( limit.getId( ), limit );
    }

    /**
     * Get the score value of this event.
     *
     * @return The score value.
     */
    public final int getScoreValue( )
    {
        return scoreValue;
    }

    /**
     * Set the score value of this event.
     *
     * @param newScoreValue The new score value.
     */
    public final void setScoreValue( final int newScoreValue )
    {
        this.scoreValue = newScoreValue;
    }


    // Serialization

    private static final String SCORE_VALUE_TAG = "score-value";
    // @compat 0.11.3
    private static final String OLD_SCORE_VALUE_TAG = "scoreValue";
    // end @compat 0.11.3


    /**
     * {@inheritDoc}
     */
    @Override
    protected void writeAttributes( FreeColXMLWriter xw ) throws XMLStreamException
    {
        super.writeAttributes( xw );

        if ( value != null )
        {
            xw.writeAttribute( VALUE_TAG, value );
        }

        if ( scoreValue != 0 )
        {
            xw.writeAttribute( SCORE_VALUE_TAG, scoreValue );
        }
    }

    /**
     * {@inheritDoc}
     */
    @Override
    protected void writeChildren( FreeColXMLWriter xw ) throws XMLStreamException
    {
        super.writeChildren( xw );

        for ( Limit limit : getLimits( ) ) limit.toXML( xw );
    }

    /**
     * {@inheritDoc}
     */
    @Override
    protected void readAttributes( FreeColXMLReader xr ) throws XMLStreamException
    {
        super.readAttributes( xr );

        value = xr.getAttribute( VALUE_TAG, ( String ) null );

        // @compat 0.11.3
        if ( xr.hasAttribute( OLD_SCORE_VALUE_TAG ) )
        {
            scoreValue = xr.getAttribute( OLD_SCORE_VALUE_TAG, 0 );
        }
        else
        // end @compat 0.11.3
        { scoreValue = xr.getAttribute( SCORE_VALUE_TAG, 0 ); }
    }

    /**
     * {@inheritDoc}
     */
    @Override
    protected void readChildren( FreeColXMLReader xr ) throws XMLStreamException
    {
        // Clear containers.
        if ( xr.shouldClearContainers( ) )
        {
            limits = null;
        }

        super.readChildren( xr );
    }

    /**
     * {@inheritDoc}
     */
    @Override
    protected void readChild( FreeColXMLReader xr ) throws XMLStreamException
    {
        final Specification spec = getSpecification( );
        final String tag = xr.getLocalName( );

        if ( Limit.getXMLElementTagName( ).equals( tag ) )
        {
            Limit limit = new Limit( xr, spec );
            // @compat 0.10.5
            if ( "model.limit.independence.colonies".equals( limit.getId( ) ) )
            {
                limit.setId( "model.limit.independence.coastalColonies" );
                limit.getLeftHandSide( ).setMethodName( "isConnectedPort" );
            }
            // end @compat
            addLimit( limit );

        }
        else
        {
            super.readChild( xr );
        }
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public String getXMLTagName( ) { return getXMLElementTagName( ); }

    /**
     * Gets the tag name of the root element representing this object.
     *
     * @return "event".
     */
    public static String getXMLElementTagName( )
    {
        return "event";
    }
}
